1. Field of the Invention
This invention relates to an optical disk player such as a compact disk player and, more particularly, to an optical pickup feed unit of the type in which an optical pickup facing opposite an optical disk is moved together with a rack by the motive force of a motor.
2. Description of the Prior Art
FIG. 3 is a plan view showing an optical pickup feed unit of a conventional compact disk player.
Reference numeral 1 designates a drive chassis. On the underside of this drive chassis 1 is provided a spindle motor 2. This spindle motor 2 is used to drive a turntable 3 disposed on the upper side of the chassis, by the driving force of this motor an optical disk D (not shown) placed on the turntable 3 is driven to rotate. Inside a cutout (not shown) formed in the drive chassis 1 is provided an optical pickup 5 having an objective lens 4 facing opposite the optical disk D, which is movable in the directions of X and Y. One side face 5a of the optical pickup 5 has a rack 6 secured thereto which is movable on the underside of the drive chassis 1. On the underside of the drive chassis 1 is further provided a feed motor 7. A rotary shaft 7a projecting from this feed motor 7 has a worm 8 secured thereto. The turning force of the feed motor 7 is transmitted from the worm 8 via a gear group (not shown) including reduction gears and a pinion to the rack 6, so that the photopickup 5 is driven together with the rack 6 in the directions of X and Y. In response to driving of the photopickup 5, a detecting beam spot emitted from the objective lens 4 scans the recording tracks of the optical disk D to read the record of the optical disk D.
According to the foregoing structure of the prior art, the rack 6 needs a certain length to cause the photopickup 5 to move within the extent of the radius of the optical disk D. In this connection, since the rack 6 has the same height as that of the spindle motor 2 on the underside of the drive chassis 1, the movable space of the rack 6 must be laid out in an area devoid of the spindle motor 2. In view of the above, as shown in FIG. 3, the movable space of the right-hand end 6a in the drawing of the rack 6 was laid out adjacent to one side of the spindle motor 2 in the prior art. Thus, the spindle motor 2 and the feed motor 7 are disposed with leaving a spacing therebetween to permit passage of the right-hand end 6a of the rack 6, and the width dimension Wa of the drive chassis 1 is made large by the extent of the movable space of the right-hand end 6a of the rack 6.
On the other hand, if the rack 6 is disposed on an operating line crossing the spindle motor 2 as shown in FIG. 4, it is possible to make narrow the spacing between the spindle motor 2 and the feed motor 7 to thereby shorten the width dimension Wa of the drive chassis 1. In this case, however, when the optical pickup 5 is driven in the direction of X and moved up to a position remotest from the turntable 3, the left-hand end 6b of the rack 6 projects from the drive chassis 1. Such projection of the left-hand end 6b of the rack 6 becomes an hindrance in designing the body of the optical disk player in which the drive chassis 1 is assembled.